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/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/seqlock.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
struct nft_counter {
seqlock_t lock;
u64 bytes;
u64 packets;
};
static void nft_counter_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
struct nft_counter *priv = nft_expr_priv(expr);
write_seqlock_bh(&priv->lock);
priv->bytes += pkt->skb->len;
priv->packets++;
write_sequnlock_bh(&priv->lock);
}
static int nft_counter_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
struct nft_counter *priv = nft_expr_priv(expr);
unsigned int seq;
u64 bytes;
u64 packets;
do {
seq = read_seqbegin(&priv->lock);
bytes = priv->bytes;
packets = priv->packets;
} while (read_seqretry(&priv->lock, seq));
if (nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(bytes)))
goto nla_put_failure;
if (nla_put_be64(skb, NFTA_COUNTER_PACKETS, cpu_to_be64(packets)))
goto nla_put_failure;
return 0;
nla_put_failure:
return -1;
}
static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = {
[NFTA_COUNTER_PACKETS] = { .type = NLA_U64 },
[NFTA_COUNTER_BYTES] = { .type = NLA_U64 },
};
static int nft_counter_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_counter *priv = nft_expr_priv(expr);
if (tb[NFTA_COUNTER_PACKETS])
priv->packets = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_PACKETS]));
if (tb[NFTA_COUNTER_BYTES])
priv->bytes = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_BYTES]));
seqlock_init(&priv->lock);
return 0;
}
static struct nft_expr_type nft_counter_type;
static const struct nft_expr_ops nft_counter_ops = {
.type = &nft_counter_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_counter)),
.eval = nft_counter_eval,
.init = nft_counter_init,
.dump = nft_counter_dump,
};
static struct nft_expr_type nft_counter_type __read_mostly = {
.name = "counter",
.ops = &nft_counter_ops,
.policy = nft_counter_policy,
.maxattr = NFTA_COUNTER_MAX,
.flags = NFT_EXPR_STATEFUL,
.owner = THIS_MODULE,
};
static int __init nft_counter_module_init(void)
{
return nft_register_expr(&nft_counter_type);
}
static void __exit nft_counter_module_exit(void)
{
nft_unregister_expr(&nft_counter_type);
}
module_init(nft_counter_module_init);
module_exit(nft_counter_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_EXPR("counter");
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